PROMISSORY NOTE

          If any payment shall be due on a Saturday or Sunday or upon any other day on which state or national banks in the State of Oklahoma are closed for business by virtue of a legal holiday for such banks, such payment shall be due and payable on the next succeeding banking day and interest shall accrue to such day. All interest due hereon shall be computed on the actual number of days elapsed (365 or 366) based upon a 360-day year.

          All payments under this Note shall be made in legal tender of the United States of America or in other immediately available funds at Lender’s office described above, and no credit shall be given for any payment received by check, draft or other instrument or item until such time as the holder hereof shall have received credit therefor from the holder’s collecting agent or, in the event no collecting agent is used, from the bank or other financial institution upon which said check, draft or other instrument or item is drawn.

          From time to time the maturity date of this Note may be extended or this Note may be renewed, in whole or in part, or a new note of different form may be substituted for this Note and/or the rate of interest may be changed, or changes may be made in consideration of loan extensions, and the holder, from time to time, may waive or surrender, either in whole or in part, any rights, guarantees, security interests or liens given for the benefit of the holder in connection herewith; but no such occurrences shall in any manner affect, limit, modify or otherwise impair any rights, guarantees or security of the holder not specifically waived, released or surrendered in writing, nor shall any maker, guarantor, endorser or any person who is or might be liable hereon, either primarily or contingently, be released from such liability by reason of the occurrence of any such event. The holder hereof, from time to time, shall have the unlimited right to release any person who might be liable hereon; and such release shall not affect or discharge the liability of any other person who is or might be liable hereon.

          If any payment required by this Note to be made is not made when due, or if any default occurs under any loan agreement or under the provisions of any mortgage, security agreement, assignment, pledge or other document or agreement which provides security for the indebtedness evidenced by this Note, the holder hereof may, at its option, without notice or demand, declare this Note in default and all indebtedness due and owing hereunder immediately due and payable. Interest from the date of default on such principal balance and on any past due interest hereunder shall accrue at the rate of five percent (5%) per annum above the nondefault interest rate accruing hereunder. The Maker and any endorsers, guarantors and sureties hereby severally waive protest, presentment, demand, and notice of protest and nonpayment in case this Note or any payment due hereunder is not paid when due; and they agree to any renewal, extension, acceleration, postponement of the time of payment, substitution, exchange or release of collateral and to the release of any party or person primarily or contingently liable without prejudice to the holder and without notice to the Maker or any endorser, guarantor or surety. Maker and any guarantor, endorser, surety or any other person who is or may become liable hereon will, on demand, pay all costs of collection, including reasonable attorney fees of the holder hereof in attempting to enforce payment of this Note and reasonable attorney fees for defending the validity of any document securing this Note as a valid first and prior lien.

          Upon the occurrence of any default hereunder, Lender shall have the right, immediately and without further action by it, to set off against this Note all money owed by Lender in any capacity to the Maker or any guarantor, endorser or other person who is or might be liable for payment hereof, whether or not due, and also to set off against all other liabilities of Maker to Lender all money owed by Lender in any capacity to Maker, and Lender shall be deemed to have exercised such right of setoff and to have made a charge against such money immediately upon the occurrence of such default even though such charge is made or entered into the books of Lender subsequently thereto.

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